A Bit of Blue

A case posted to the IDS forum by Baker Ron

age 31 years, sex: m, location: trunk

Clinical history: 3 recent cases, in each the dermoscopy image is first, then the clinical image. 1st is a 31 year old male who is not sure how long he has had the lesion but has noticed it get darker in recent months. 2nd is a 65 year old male who was not really very aware of the lesion on the back of his arm but thinks it may have been there a few months. The 3rd is a 37 year old female who noticed the lesion appear and grow to the current size about a year ago, then it appears to have remained stable since then.

Diagnosis: Histology is now available on 2 of these. I expected a combined nevus on the 1st, was quite unsure about the 2nd, and have been more confident about the 3rd.

Question: What do you think these are?

Comments:

Landi Christian:

1. combined nevus for me too

2. baso-squamous carcinoma> melanoma

3. melanoma metastasis > blue nevus

Thanks for the post, Ron.

Burns John:

1. combined

2. NMSC vs melnaoma

3. blue nevus

Thx for the cases

Pyne John:

1 Agree, combined.

2 History uncertain. Could be anything from a bit of spindle cell mischief to an insect bite.

3 Deep located? blue naevus. Out of focus so could be short on cellular mass/pigment or deep location, or both.

Not long to go to “Ho Ho Ho” time. The reindeer are restless and Santa is keen to deliver!

All the best to the big IDS family for christmas and a happy new 2014.

Bartalini Paolo:

Hi to all.

1 – combined nevus

2 – MM vs NMSC ( 2:1 )

3 – Blue nevus vs MELTUMP

Baker Ron:

1) Reported as a compound nevus. “Groups of epithelioid melanocytes are present among the naevus cells, together with abundant melanophages. There is no malignancy.” I expected a combined nevus, excised of course to exclude the usual.

2) Sections show foreign material consistent with plant material surrounded by abundant polymorphs and macrophages. There is no evidence of malignancy. I think the dermoscopy is consistent with that and you were sniffing around in the right direction, JP. The patient must have got this in the garden but gave no history to suggest that.

3) This patient is my niece, and the lesion has not been excised. There are times when even blue can be observed safely. The other lesions had histology reports arrive within the past week, but this lesion’s photos are from July. She gave a history of the lesion growing reasonably quickly to this size a year or more ago, then stopping and being stable, and it being a common location and age for a blue nevus to appear, and having the right history and appearance, we agreed to leave it there. She has no reason to have a melanoma met and a met would continue to grow, which this has not done. Also excising a met would not save her. I can’t see it as a primary.

I can easily grab my scope and laptop and compare the appearance anytime, and it is perfectly stable.